docs: def index(request):
      """
      Listing page for event `Occurrence`s.
  
      :param request: Django request object.
      :param is_preview: Should the listing page be generated as a preview? This
                         will allow preview specific actions to be done in the
                         template such as turning off tracking options or adding
                         links to the admin.
      :return: TemplateResponse
      """
      warnings.warn(
          "icekit_events.views.index is deprecated and will disappear in a "
          "future version. If you need this code, copy it into your project."
          , DeprecationWarning
      )
  
      occurrences = models.Occurrence.objects.visible()
      context = {
          'occurrences': occurrences,
      }
      return TemplateResponse(request, 'icekit_events/index.html', context)